Re: [boost] [xint] Boost.XInt formal review

Subject: Re: [boost] [xint] Boost.XInt formal review
From: Chad Nelson (chad.thecomfychair_at_[hidden])
Date: 2011-03-05 16:56:41

On Sat, 05 Mar 2011 20:07:05 +0100
Mathias Gaunard <mathias.gaunard_at_[hidden]> wrote:

>> That complicates the interface significantly, and would be completely
>> unnecessary once the library matures enough to have faster
>> multiplication algorithms.
>
> You're forgetting several things here: first, some algorithms might
> be faster than others depending on the situation, and second, you'd
> have to include dependency on FFTW in the core of the library to
> provide the fastest solution.

"Fastest Fourier Transform in the West"? If it lives up to its name
(which reviews indicate that it does), that would indeed be preferable
for speed for really large numbers. And with the incompatible license,
it couldn't be included in XInt.

That's probably the best argument for exposing the internals that I've
seen yet.

>> The cost of freezing the internals at a 1.0 level, or of breaking
>> client code when the interface has to change. [...]
>
> I thought you had agreed that separating data and algorithms was a
> good idea in another thread, since many people were pointing it out,
> is that not correct? [...]

I did agree that it's a good idea for the future, but I don't want to
do that at this point in XInt's existence, for the reason I stated
above.

>> I don't know what culture you grew up in [...]
>
> I am sorry you feel this way. But please realize that you failed to
> provide reasons when I asked for them.

I did so under the mistaken impression that you were being deliberately
malicious. I now believe I was wrong, and I apologize. If you're
willing, I'd like to start fresh.

>> The only competing library that matters, so far as I can see, is GMP.
>> And GMP has licensing issues, which is the main reason why I started
>> writing XInt in the first place -- I didn't originally write it for
>> Boost, I wrote it for use in one of my own commercial projects.
>
> A quick google search shows quite a few C and C++ libraries that 
> implement big integer facilities under a liberal license (though LGPL 
> isn't that restrictive in the first place).
>
> Most of them only provide fixed size though.

And I believe GMP is the one that it will be compared to in most
people's minds.

>> That's sufficient reason right there
>
> Wouldn't that be up to the reviewers to decide?

Sorry, I should have said "that's sufficient reason for me". The
licensing issue isn't as bad as I thought, I was under the impression
that it was GPL-licensed, not LGPL. But even had I known that earlier,
it wouldn't have stopped me from writing XInt, for the reason of
interface.
-- 
Chad Nelson
Oak Circle Software, Inc.
*
*
*